#include<iostream>
using namespace std;
int main ()
{
    int i;
    char l,a,p2;
    string letras;
    a='a';
    i=0;

    cout<<a<<endl;
    while (i<2)
    {
        i=i+1;
        cout<<a<<endl;
        a=a+1;
        cout<<a<<endl;


    }
    return 1;
}
